Correlation between recrystallization texture and heterogeneities in deformed structure of an electrical steel by electron back-scatter diffraction

Abstract

The correlation of recrystallization nucleation and the deformation microstructure in an electrical steel was studied by examining micro-indenter marked specimens with electron back-scatter diffraction (EBSD). The deformed grains were classified according to the density of high-angle boundaries in the grain interiors, and the local misorientation of substructure was characterized by using both the kernel average misorientation (KAM) and the high misorientation region (HMR) analyses. The EBSD observation confirmed that recrystallization was preferentially evolved from areas having high local misorientation revealed by HMRs. The recrystallization nuclei in partially recrystallized specimen were observed to be directly related to the high-KAM areas in the deformed grains. The orientation distribution of the areas having high local misorientation in the cold-rolled structure, which fulfill both criteria of high-KAM and HMR, was found to be associated with the texture of recrystallized grains.